The U.N. refugee agency says it is concerned about the worsening situation in the eastern part of Sri Lanka. It says there has been a significant increase in recent months in the numbers of killings, abductions and injuries in places where Tamil internally displaced people and refugees have returned.

During the past two years, most of the more than 200,000 people displaced by fighting in the eastern districts of Trincomalee and Batticaloa have returned home.

The U.N. refugee agency and other humanitarian agencies have been supporting the Sri Lankan government as it reintegrates them to their communities.

UNHCR Spokesman Ron Redmond says aid agencies have been working to provide the returnees with shelter, jobs and non-food relief items. He says the recent series of killings, abductions and injuries in eastern Sri Lanka is very worrying and is putting the return process at risk.

"In November, the U.N. recorded 24 civilian deaths, just in the Batticaloa district of the East. And, UNHCR is asking that the Sri Lankan government and the authorities in the area investigate these developments seriously," he said. "And, that they effectively investigate it and we urge the authorities provide adequate security to all the civilians living in these areas."

Redmond says there are many armed groups running around in this area, making it a difficult to ensure security. Nevertheless, he says something must be done to ensure the safety of the people.

He says returnees in the Batticaloa area report they increasingly feel intimidated and face restrictions on their movement. He says this limits their ability to support themselves and their families.

He says more than 50 families have already left their villages due to fear and insecurity. Others, he says are no longer sleeping in their own homes. Instead, several families gather in one house at night for security.

The Tamil Tigers have been fighting for an independent state for the past 25 years. The Sri Lankan government recently has made important gains in this long-running civil war and appears to be gaining the upper hand.

Redmond says the UNHCR is closely monitoring the rapidly developing situation in the north of the country. He notes about one-quarter of a million people remain displaced there due to the ongoing conflict.